Preheat oven to 425.

• Drizzle one Tablespoon olive oil over a large baking sheet or baking dish. Halve the tomatoes, if using Roma tomatoes, and cube if using larger beef steak tomatoes. Toss the tomatoes and quartered onion with salt, pepper and the remaining olive oil, then add unpeeled garlic cloves and stir gently to coat.
• Spread the veggies (*see note below) onto the greased baking sheet and then roast for 25 minutes, until the tomato skins have shriveled and the garlic is soft. Remove the veggies from the heat and allow to cool.
• Remove the cooled garlic from skins and place into a 4-7 quart crockpot/slow cooker along with the tomatoes, onions and any remaining juice. Add vegetable broth and tomato paste, then stir to combine the paste into the broth
• Add bay leaf and fresh basil and parsley (optional), then cover and cook on low for 4-6 hours or on high for 2-3 hours.
• Discard the bay leaf, then working in batches, puree the tomato soup with a blender or food processor until smooth. Return the pureed soup to the slow cooker and stir in lemon juice and brown sugar. Serve the tomato soup with heavy cream (or whole milk) and fresh basil (optional).